The articles explains a home-built ELC circuit which may be used for regulating the speed and frequency of a windmill generator unit. The idea was requested by Mr. Nilesh Patil.
I am Great fan of your Electronic circuits and Hobby to create it. Basically i'm from rural area where 15 hours power cut off problem we facing every year
Even if i go for to buy inverter that is also not get charged due to power failure.
I have created wind mill generator (In Very Cheap Cost ) from that will support to charge 12 v battery.
For the same i m looking to buy wind mill charge turbine Controller that is too costly.
So planned to create our own if have suitable design from you
Generator Capacity : 0 - 230 AC Volt
input 0 - 230 v AC (Vary depends on wind speed)
output : 12 V DC (sufficient boost up current).
Overload / Discharge / Dummy Load handling
Can you please suggest or help me to develop it and required component & PCB from you
I May required many same circuit once succeed.
The Circuit Design
The design requested above can be implemented simply by using a step down transformer and a LM338 regulator as already discussed in many of my posts earlier.
The circuit design explained below is not relevant to the above request, rather addresses a much complex issue in situations where a windmill generator is used for operating AC loads assigned with mains 50Hz or 60Hz frequency specifications.
How an ELC Works
An electronic load controller is a device which frees or chokes up the speed of an associated electricity generator motor by adjusting the switching of a group of dummy or dump loads connected parallel with the actual usable loads.
The above operations become necessary because the concerned generator may be driven by an irregular, varying source such as a flowing water from a creek, river, waterfall or through wind.
Since the above forces could vary significantly depending upon the associated parameters governing their magnitudes, the generator could also be forced to increase or decrease its speed accordingly.
An increase in speed would mean an increase in voltage and frequency which in turn could be subjected to the connected loads, causing undesirable effects and damage to the loads.
Adding Dump Loads
By adding or deducting external loads (dump loads) across the generator, its speed could be effectively countered against the forced source energy such that the generator speed is maintained approximately to the specified levels of frequency and voltage.
I have already discussed a simple and effective electronic load controller circuit in one of my previous posts, the present idea is inspired from it and is quite similar to that design.
The figure below shows how the proposed ELC may be configured.
The heart of the circuit is the IC LM3915 which is basically a dot/bar LED driver used for displaying variations in the fed analogue voltage input through sequential LED illuminations.
The above function of the IC has been exploited here for implementing the ELC functions.
The generator 220V is first stepped down to 12V DC through a step down transformer and is used for powering the electronic circuit consisting the IC LM3915 and the associated network.
This rectified voltage is also fed to pin#5 of the IC which is the sensing input of the IC.
Generating Proportionate Sensing Voltages
If we assume the 12V from the transformer to be proportionate with 240V from the generator, implies that if the generator voltage rises to 250V would increase the 12V from the transformer proportionately to:
12/x = 240/250
x = 12.5V
Similarly if the generator voltage drops to 220V would proportionately drop the transformer voltage to:
12/x = 240/220
x = 11V
and so on.
The above calculations clearly show that the RPM, frequency and voltage of the generator are extremely linear and proportionate to each other.
In the proposed electronic load controller circuit design below, the rectified voltage fed to pin#5 of the IC is adjusted such that with all the usable loads switched ON, only three dummy loads: lamp#1, lamp#2 and lamp#3 are allowed to remain switched ON.
This becomes a reasonably controlled set up for the load controller, of course the adjustment variations range could be set up and adjusted to different magnitudes depending upon the users preferences and specifications.
This may be done by randomly adjusting the given preset at pin#5 of the IC or by using different sets of loads across the 10 outputs of the IC.
Setting up the ELC
Now with the above mentioned set-up let's assume the generator to be running at 240V/50Hz with the first three lamps in the IC sequence switched ON, and also all the external usable loads (appliances) switched ON.
Under this situation if a few of the appliances are switched OFF would relieve the generator from some load resulting in an increase in its speed, however the increase in the speed would also create an proportionate increase in voltage at pin#5 of the IC.
This will prompt the IC to switch ON its subsequent pinouts in the order thereby switching ON may be lamp#4,5,6 and so on until the speed of the generator is choked up in order to sustain the desired assigned speed and frequency.
Conversely, suppose if the generator speed tends to sow down due to degrading source energy conditions would prompt the IC to switch OFF lamp#1,2,3 one by one or a few of them in order to prevent the voltage from falling below the set, correct specifications.
The dummy loads are all terminated sequentially via PNP buffer transistor stages and the subsequent NPN power transistor stages.
All the PNP transistors are 2N2907 while the NPN are TIP152, which could be replaced with N-mosfets such as IRF840.
Since the above mentioned devices work only with DC, the generator output is suitably converted to DC via 10amp diode bridge for the required switching.
The lamps could be 200 watt rated, 500 watt rated or as preferred by the user, and the generator specs.